The present invention relates to a windshield wiper device of the type including a wiper arm driven by a wiper shaft and carrying a wiper blade oscillating against the windshield of a motor vehicle.
Windshield wiper devices are known, in which a lever mechanism is formed as a four-joint-parallelogram. When such a mechanism is accommodated in a housing the latter must be sealed in the region of the extension of the wiper arm into this housing to prevent possible contamination of the joints and leakage of a lubricant. Such a sealing becomes problematic because the four-joint-parallelogram transmits the displacement motion and the oscillating motion to the wiper arm which can cause in the region of the penetration of the wiper arm into the housing a "striking movement" which can be avoided by the sealing which has, however, involved considerable expenses.
It has been also known that the shifting or displacing movement of the wiper arm must be controlled by a costly gear drive which should ensure a non-objectionable shifting movement.